Start with an eligible contribution budget
The PPF contribution limit is an account constraint, not a slider that can be ignored to make a comparison attractive. Annual deposits must stay within the applicable ₹500–₹1.5 lakh range. A ₹5,000 monthly comparison corresponds to ₹60,000 a year and fits within that range.
Understand the PPF approximation
Actual PPF interest depends on the account’s eligible balance and deposit timing, including the lowest balance between the fifth and the end of the month. The comparison uses a simplified end-of-month contribution approximation. It does not reconstruct a passbook or validate a withdrawal request.
The normal PPF account term is 15 years. A longer contribution projection assumes permitted extension with deposits. Today’s rate is held constant for illustration, while future rates can be notified differently.
Compare usable money and uncertainty
A SIP describes how contributions are made, not a guaranteed product return. Mutual-fund risk and tax depend on the fund and transaction details. The PPF balance has different access restrictions and tax treatment. Compare how much could be available on the date of the actual goal, not only the highest displayed amount.
Run lower-return SIP cases and different PPF-rate scenarios. Keep the same contribution budget in each case. A comparison is useful when it reveals the trade-off between growth assumptions, liquidity and constraints; it becomes misleading when it presents a universal winner.